Process for the manufacture of carbon-black and lampblack.



J. M. GERARD.

PROCESS FOR THE MANUFACTURE OF CARBON BLACK AND LAMPBLACK.

APPLICATION FILED 0CT.8. 1917.

1 ,2'78, 1 87., Patented Sept. 10, L918.

\ 2 g WWW/05mm? I k/ K0 M 4 ATTORNEYS UNITED STATES PATNT OFFICE.

JULIAN M. GERARD, OF NEW YORK, N. Y.

PROCESS FOR THE MANUFACTURE OF CARBON-BLACK AND LAMPIBLACK.

for the Manufacture of Carbon-Black and Lampblack, specification.

My invention relates to a new and 1mproved method for the manufacture of of which the following is a lampblack.

Lampblack, as heretofore manufactured, has been chiefly made byburning natural gas, various oils, and the like, in such a manner that part of the carbon therein is consumed and the remainder is present in the gases of combustion, and collecting this unconsumed carbon usually by causing the flame to impinge upon a cooled surface. Such processes are extremely wasteful, because a large amount of the carbon is consumed in producing the heat of the flame, and a considerable amount of the unconsumed carbon cannot be collected upon the cooled surface.

According to my invention, the particles of carbon remaining after the incomplete combustion of the substances consumed, are collected by means of electrical precipitation when the gas is cooled toa suitable temperature, to be later disclosed herein, and the carbon is removed from the collecting surfaces without scraping or other mechanical movements of one particle with respect to the others. Because of the fact that the par ticles are removed from a current of the cooled gas, they collect in an extremely fine state of subdivision, so much so, that no mechanical means such as scrapers or the like, canbe used or are necessary.v In fact, experience has shown that the vibration of the air, due to a loud sound, is sufiicient to dislodge the carbon particles from their collecting surfaces. As a result of this, and because the particles are dislodged without the use of scrapers or similar means which would tend to move the carbon particles with respect to each other and compact them, a quality of lampblack is obtained of a much finer quality than that heretofore secured from the old methods above mentioned.

I have also-found it desirable and possible to divide the unconsumed carbon particles Specification of Letters Patent.

Application filed October 8, 1917. Serial No. 195,299.

Patented Sept. 10,-1 918;.

in the flame into two grades or qualities by allowing the flame to first impinge upon a cool surface as in the old method, and then collecting the remaining particles by means of electrical precipitation. By this method an especially fine quality of lampblack is secured in the precipitator.

This fine grade secured in the electrical precipit-ator is easily miscible with Water when the lampblack is made from natural gas to which my invention is particularly directed, and has an unusual brilliancy and coloring power. My invention is not limited to natural gas as the, source for the lampblack, but it may also be extended to other sources thereof, such as oils or the like.

Further objects of my invention will be set forth in the following description and drawings, which illustrate a mechanism that i may be used for carrying out my invention.

Figure 1 is, a diagrammatic cross-section along line 1-1 of Fig. 2.

Fig. .2 is a longitudinal cross-section shown diagrammatically.

Fig. 3 is a plan view.

The natural gas is led into the building 1, into the burners "16, mounted upon the supports 15. The ventilation of the building is so controlled that instead of the proportion ofair now supplied, suflicient air is supplied "to the natural gas of the kind found in the Southern part of'the United States, so as to cause it to produce between 2 and 3 pounds of lampblack per thousand cubic feet. As practically all of the lampblack particles in the fluid are "collected by the method of precipitation herein shown,

I have found it expedient in practice to cause the burning of the hydrocarbon gases to be effected with the minimum amount of. oxygen necessary to maintain combustion. The burners cause the flames which are full of unconsumed particles of carbon,

to be discharged into the packing house 5,

from the mouths of the chambers 15.

In this manner a certain amount .of the to impinge upon the cylinders 10, which are I carbon is deposited upon the cool cylinders 10, and this amount is preferably about one pound for every thousand cubic feet.

The remaining gas and particles are led into pipe 2 and then drawn through it by any suitable means. so arranged, not to disturb the ventilation of the building 1 as before mentioned. A tan 3. if desired. may be employed to cause an artificial dratt.

in this pipe 2 the flames are cooled to about -l00 degrees C. at which temperature the ionic discharge caused by the electrical precipitator causes the collection of the carbon particles in a very loose and tinely divided condition. and are thence sent through the tubes 6. in which the conductors 7 comprisino smooth. uninsulated wires. are placed along their axes. The tubes are provided. in a suitable number. so as not to supply any wire with too much gas or particles.

The vvires 'Z. ivhich are the active Q()l1(lll(3ii orsi are furnished with a unidirectional current of from fifty thousand to seventy-lite thousand volts. by electrical apparatus of suitable kind, as this "voltage. has ieen it'oun suitable for precipitating the lainpbh cl; in the finely divided form before mentioned.

is here illustrated. a current from a suitable generator 8i is sentinto a transformer comprising a primary coil 2 t and sec ondary coil :23. so that the current has its voltage raised to the required amount.

The current is then sent through a lGCilnE? or any suitable kind. and supplied therefrom o the Wire The current supplied to the vvire 7 may be altered. itdesired. Resistances and and capacities 28 and 33. sel'f-inductances 30 and ant spa a'. gaps and 27 are arranged in the secondary circuit. so that the oscillation of the proper frequency and suitable damping factors 2 produced. The corona or brush. discharge 1 produced. a disruptive discharge being avoided. If the carbon deposit becomes too heavy. so that there is danger oi? a disruptive discharge. then some ct tile de posit is removed while the electrical pro ipitation is temporarily stopped.

lfnder ordinary circumstances. gravity a sli ehtv vibration. removes the deposit v7" sutficient rapidity to prevent a disrupt .a discharge. If disruptive diucharge is caused by the collection of the particles upon the wires 1', the polarity thereof is tor orarily reversed. which causes the cleari of the Wire 7 of the accumulation thereon. Even if a disruptive discharge does ta I place. it has little or no effect upon tile EX- trenie fineness of the deposits.

.L lie-building 5, "which constitutes thepaceing house, is connected to the ground so iat the tubes are also soconnected. and serve collectors. The cylinders 10 made of nickel. zinc or copper, or some other non oxidizing material. A sheet of gauze it? may be interposed between the flames and the cylinders 10. to ool the flames. instead ot the speciiic means for producing a high tension current for the brush or corona discharge above mentioned. any welldinown means may be employed. and an alternating current may be used.

I claim:

1. A method of producing lanipblaclt which consists in electrically precipitating the UHOXldlZQtl carbon particles suspended in the gaseous products resulting from the incomplete oxidation of a hydrocarbon. the

voltage employed in said precipitation being such that the said unoxidized carbon is collected in a linely divided form.

2. A method of producin lampblacl: which consists in electrically precipitating unoitidized carbon particles suspended in the gaseous products resulting from the incomplete oxidation of a hydrocarbon. the ten perature of said carbon iarticles suspended in the gaseous products being less han the, temperature at which the said oxidation took plac the voltage employed in said precigitation being such that the sa un onsumed carbon is collected in a finely divided In. the art of producing that step in the art which consists cally precipitating carbon suspeiaioed .ir a

in such a finely divided form that i recipitated particles can. be removed it i out moying them with respect to ea h other and Without a disruptive discharge, 1 employed in said precipitate.

a it in titty thousand to eventy-five a ts, the electric discharge used her a non-disruptive character.

. the art of producing lampblacln that step in the are which consists in elec trically precipitating carbon particles sum in such a finely divided pended in a gas 1 71 T7 1 term that the particles .oe GlBGiQQ' without removing them with respe other and Without a disruptive and dislodging the precipitated car-con with out agitating them with respect to each other the electric discharge used in said precipitation being of a non-disruptive character.

5. A method of producing lain. he incomplete combustion of a h n which the gaseous products from the incomplete oxidation of a hvdrocarbon and containing from too t pounds of suspended tlllOXidlZQCl car ticles for 1000 cubic feet. are caused ostz pine e upon a cool surface until sul tially one pound of said carbon par per every 1000 cubic feet of the sail products is collected and then electrically precipitating the remainder of l 'unoxidined carbon particles, the voltage 1 em loyed electrical precipitation g such,

that the carbon is collected in a finely divided form.

61% In the art of producing lampblack, that step in the art which consists in electrically precipitating unconsumed carbon suspended in a gas, the collecting surface being at zero potential, and the voltage employed being such that the carbon is collected in a finely divided form.

7. A method of producing lampblack which consists in electrically precipitating the unoxidized carbon particles suspended in the gaseous products resulting from the incomplete oxidation of a hydrocarbon, said gaseous products being cooled to substantially 400 C. before the said electrical precipitation takes place, the voltage employed in said precipitation being such that the unoxidized carbon particles are collected in a loose and finely divided form.

In testimony whereof I hereunto aflix my signature.

JULIAN M. GERARD. 

